Hans... I don't think you have "fish eye".. I think you have "solvent popping" , this occurs when the first coat is not dry enough, and the 2nd coat goes on to quick. The first coat has not had time to let all the solvent evaporate out of the paint, then the 2nd coat traps the solvent, and then it pops up thru the top coat. You can get this even if you put only "1" coat on.. as a few heavy passes can create 2 coats..
Was this color a gloss color ? was it humid that day? or muggy? rainy ? .etc..?,,, this can aggravate it..
The reason I say, this is that your pops, are very consistant over all the model.. not in a few locations..